OSI MODEL NOTES

QUESTION: Explain the OSI model with Diagram?

OSI MODEL

The International Standards Organization, the OSI, or Open System Interconnection, model was created (by ISO). It provides a layered networking framework that describes how communications across computer networks should be done. It consists of seven linked layers. 

The International Organization for Standardization (IOS) developed the open systems interconnection (OSI) model, a conceptual framework that enables various communication systems to exchange data via agreed-upon protocols. The OSI, or Open Systems Interconnection, offers a standard for multiple computer systems to communicate with one another.

The following diagram illustrates the seven OSI Model layers: the physical layer, data connection layer, network layer, transport layer, session layer, presentation layer, and application layer.

7 LAYERS OF THE OSI MODEL

The fundamental elements of every one of the layers are as per the following 

Physical Layer: 

Its capability is to send individual bits beginning with one node and then onto the next over a physical medium.

PHYSICAL LAYER OF THE OSI MODEL

Data Link Layer 

This network layer is responsible for transferring reliable data connected by the physical layer from one node to another.

THE DATA LINK LAYER OF THE OSI MODEL

Network Layer 

This Network layer takes transfers the data packets individually from the source to the destination through appropriate routing and addressing. 

THE NETWORK LAYER OF THE OSI MODEL

Transport Layer 

It is responsible for transporting the entire message from the source host to the destination host.

THE TRANSPORT LAYER OF THE OSI MODEL

Session Layer 

It establishes sessions between users and offers services like dialog control and management. 

THE SESSION LAYER OF THE OSI MODEL

Presentation Layer 

It monitors the syntax and semantics of transmitted information through encryption, compression, and translation.

THE PRESENTATION LAYER OF THE OSI MODEL

Application Layer 

It provides high-level APIs (application program interfaces) to users wide.

THE APPLICATION LAYER OF THE OSI MODEL

QUESTION: Which layer of the OSI model is responsible for routing information between computers? 

Ans: The two main functions of the network layer. One is breaking up parts into network packets, and collecting the packets on the getting end. The other is routing packets, the network layer uses network addresses (typically Internet Protocol addresses) to route packets to a destination node. This is done by discovering the best path across a physical network.

QUESTION: What are the advantages and disadvantages of Fiber Optic Cable?

 THE ADVANTAGES OF FIBRE OPTIC CABLE

• it provides significantly improved performance when it comes to bandwidth.
• Fiber optic cables carry signals over much longer distances than traditional cabling with a minimum power loss.
• Optical fibers are much smaller diameters i,e  thinner and lighter than copper and other wires.
• Due to how thin the fibers are, more of them can fit into a given-diameter cable as compared to copper wires.
• it also helps to enhance the cable’s ability to transfer data quickly over longer distances without suffering considerable signal degradation.
• electrical signals or light signals from one fiber don’t interfere with those of other fibers.
• Fiber optics offer a level of safety that simply cannot be matched by other materials

 THE DISADVANTAGES OF FIBRE OPTIC CABLE

•         The cost of copper cabling is smaller than that of fiber optics wire.
•         If we bend fiber optics wire them too much, they will break.
•        Fiber optics wires can be broken or have transmission losses when enfolded around curves.
•         The optical fibers are more expensive to install.